whenever(project.extensions)
            .thenReturn(convention)
        whenever(project.convention)
            .thenReturn(convention)
        whenever(convention.getByType(eq(conventionType)))
            .thenThrow(UnknownDomainObjectException::class.java)

        try {
            project.the<CustomConvention>()
            fail("UnknownDomainObjectException not thrown")
        } catch (ex: UnknownDomainObjectException) {